Mplus VERSION 2.12
MUTHEN & MUTHEN
04/28/2003   1:39 PM

INPUT INSTRUCTIONS

  ! INPUT FILE FOR EXAMPLE 2 from BG MS # 020404 by C Prescott
  TITLE:          2-group Univariate Twin Model for a Binary Variable (DELTA param

  DATA:       FILE = example1.dat;

  VARIABLE:         NAMES = famno zyg y1 y2;
                        USEVARIABLEs = y1 y2;
                      GROUP = zyg(1=mz 2=dz);
                      CATEGORICAL = y1 y2;

  DEFINE:     CUT y1(110); CUT y2(110);

  ANALYSIS:         TYPE = MEANSTRUCTURE;
              PARAM = DELTA;               ! default method

  MODEL:                              ! set up default values for all groups
   [y1$1 y2$1] (1);                                     ! thresholds
   {y1@1 y2@1};                       ! fix scaling factors to 1

   a1 BY y1*.6 (11); a2 BY y2*.6 (11);     ! additive genetic loadings
   c1 BY y1*.3 (12); c2 BY y2*.3 (12);     ! common envt loadings

   [a1-c2@0];                             ! fix latent variable means=0
    a1-c2@1;                              ! fix latent variable vars=1
    a1-a2 WITH c1-c2@0;                ! latent variable correlations
    a1 WITH a2@1; c1 WITH c2@1;

  MODEL dz:                           ! parameters which differ from 1st group
   a1 WITH a2@0.5;

  OUTPUT: SAMP RES STAND;



INPUT READING TERMINATED NORMALLY



2-group Univariate Twin Model for a Binary Variable (DELTA param)

SUMMARY OF ANALYSIS

Number of groups                                          2
Number of observations
   Group MZ                                            1000
   Group DZ                                            1000

Number of y-variables                                     2
Number of x-variables                                     0
Number of continuous latent variables                     4

Observed variables in the analysis
   Y1          Y2

  Grouping variable     ZYG

  Categorical variables
   Y1          Y2

Continuous latent variables in the analysis
   A1          A2          C1          C2


Estimator                                             WLSMV
Maximum number of iterations                           1000
Convergence criterion                             0.500D-04
Parameterization                                      DELTA

Input data file(s)
  example1.dat

Input data format  FREE


SAMPLE STATISTICS


     ESTIMATED SAMPLE STATISTICS FOR MZ


           SAMPLE THRESHOLDS
              Y1$1          Y2$1
              ________      ________
      1         1.054         1.098


           SAMPLE TETRACHORIC CORRELATIONS
              Y1            Y2
              ________      ________
 Y1
 Y2             0.581


     ESTIMATED SAMPLE STATISTICS FOR DZ


           SAMPLE THRESHOLDS
              Y1$1          Y2$1
              ________      ________
      1         1.094         1.041


           SAMPLE TETRACHORIC CORRELATIONS
              Y1            Y2
              ________      ________
 Y1
 Y2             0.323


THE MODEL ESTIMATION TERMINATED NORMALLY



TESTS OF MODEL FIT

Chi-Square Test of Model Fit

          Value                              1.126*
          Degrees of Freedom                     3**
          P-Value                           0.7705

*  The chi-square value for MLM, MLR, MLMV, WLSM and WLSMV cannot be used for
   chi-square difference tests.  MLM and MLR chi-square difference testing is
   described on page 360 in the Mplus User's Guide.

** The degrees of freedom for MLMV and WLSMV are estimated according to
   formula 110 (page 358) in the Mplus User's Guide.

Chi-Square Test of Model Fit for the Baseline Model

          Value                            149.825
          Degrees of Freedom                     2
          P-Value                           0.0000

CFI/TLI

          CFI                                1.000
          TLI                                1.008

RMSEA (Root Mean Square Error Of Approximation)

          Estimate                           0.000

WRMR (Weighted Root Mean Square Residual)

          Value                              0.587



MODEL RESULTS

                   Estimates     S.E.  Est./S.E.    Std     StdYX

Group MZ

 A1       BY
    Y1                 0.718    0.117      6.154    0.718    0.718

 A2       BY
    Y2                 0.718    0.117      6.154    0.718    0.718

 C1       BY
    Y1                 0.255    0.278      0.919    0.255    0.255

 C2       BY
    Y2                 0.255    0.278      0.919    0.255    0.255

 A1       WITH
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000
    A2                 1.000    0.000      0.000    1.000    1.000

 A2       WITH
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000

 C1       WITH
    C2                 1.000    0.000      0.000    1.000    1.000

 Means
    A1                 0.000    0.000      0.000    0.000    0.000
    A2                 0.000    0.000      0.000    0.000    0.000
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000

 Thresholds
    Y1$1               1.071    0.027     39.080    1.071    1.071
    Y2$1               1.071    0.027     39.080    1.071    1.071

 Variances
    A1                 1.000    0.000      0.000    1.000    1.000
    A2                 1.000    0.000      0.000    1.000    1.000
    C1                 1.000    0.000      0.000    1.000    1.000
    C2                 1.000    0.000      0.000    1.000    1.000

 Scales
    Y1                 1.000    0.000      0.000    1.000    1.000
    Y2                 1.000    0.000      0.000    1.000    1.000

Group DZ

 A1       BY
    Y1                 0.718    0.117      6.154    0.718    0.718

 A2       BY
    Y2                 0.718    0.117      6.154    0.718    0.718

 C1       BY
    Y1                 0.255    0.278      0.919    0.255    0.255

 C2       BY
    Y2                 0.255    0.278      0.919    0.255    0.255

 A1       WITH
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000
    A2                 0.500    0.000      0.000    0.500    0.500

 A2       WITH
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000

 C1       WITH
    C2                 1.000    0.000      0.000    1.000    1.000

 Means
    A1                 0.000    0.000      0.000    0.000    0.000
    A2                 0.000    0.000      0.000    0.000    0.000
    C1                 0.000    0.000      0.000    0.000    0.000
    C2                 0.000    0.000      0.000    0.000    0.000

 Thresholds
    Y1$1               1.071    0.027     39.080    1.071    1.071
    Y2$1               1.071    0.027     39.080    1.071    1.071

 Variances
    A1                 1.000    0.000      0.000    1.000    1.000
    A2                 1.000    0.000      0.000    1.000    1.000
    C1                 1.000    0.000      0.000    1.000    1.000
    C2                 1.000    0.000      0.000    1.000    1.000

 Scales
    Y1                 1.000    0.000      0.000    1.000    1.000
    Y2                 1.000    0.000      0.000    1.000    1.000


R-SQUARE

Group MZ

    Observed  Residual
    Variable  Variance  R-Square

    Y1           0.419     0.581
    Y2           0.419     0.581

Group DZ

    Observed  Residual
    Variable  Variance  R-Square

    Y1           0.419     0.581
    Y2           0.419     0.581


RESIDUAL OUTPUT


     ESTIMATED MODEL AND RESIDUALS (OBSERVED - ESTIMATED) FOR MZ


           Model Estimated Means/Intercepts/Thresholds
              Y1$1          Y2$1
              ________      ________
      1         1.071         1.071


           Residuals for Means/Intercepts/Thresholds
              Y1$1          Y2$1
              ________      ________
      1        -0.017         0.027


           Model Estimated Covariances/Correlations/Residual Correlations
              Y1            Y2
              ________      ________
 Y1
 Y2             0.581


           Residuals for Covariances/Correlations/Residual Correlations
              Y1            Y2
              ________      ________
 Y1
 Y2             0.000


     ESTIMATED MODEL AND RESIDUALS (OBSERVED - ESTIMATED) FOR DZ


           Model Estimated Means/Intercepts/Thresholds
              Y1$1          Y2$1
              ________      ________
      1         1.071         1.071


           Residuals for Means/Intercepts/Thresholds
              Y1$1          Y2$1
              ________      ________
      1         0.023        -0.031


           Model Estimated Covariances/Correlations/Residual Correlations
              Y1            Y2
              ________      ________
 Y1
 Y2             0.323


           Residuals for Covariances/Correlations/Residual Correlations
              Y1            Y2
              ________      ________
 Y1
 Y2             0.000


     Beginning Time:  13:39:37
        Ending Time:  13:39:38
       Elapsed Time:  00:00:01



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